Frequency-meter.



' No 831,180. PATENTED SEPT. 18, 1906.

' E. MOGARVEY.

FREQUENCY METER.

APPLICATION FILED DEC. 7. 1904.

4 SHEETS-SHEET 1.

No. 831,180. PATENTED SEPT. 18, 1906.

E. MQGABVEY.

FREQUENCY METER.

APPLICATION FILED DBO.7, 1904.

4 SHEETS-SHEET 2.

1 l Wabzasses 9 2 Ihvenian PATENTED SEPT. 18, 1906.

E. MOGARVEY. FREQUENCY METER. APPLIOATION FILED DBO. 7. 1904.

4 SHEETS-SHEET 3.

No. 831,180. I PATENTED SEPT. 18, 1906. E. McGrARVEY.v

FREQUENCY METER.

APPLICATION FILED DEO.7,1904.

4 SHEETS-SHEET 4.

, "and '.u'sefu'l Improvements in I NITED; sTATEs 19 mm OFFICE. I n

. EDWARD McG-AR-VEY, oF'BELLEroNrE, PENNSYLVANIA.

FREQUENCY-METER.

Be it known that I, EDWARD YMGGARVEY, a

,citizjenfof] the United States, residing; at 'Bellefonte', inthe countyof Center. and State of-Penn'sylvania, have inventedcertain newrequen'cy-Me ters, ofwhich'the following is a specification, j referencebeingghad "therein to theaccom frequencymieter.

- p'anying drav'rings, formingpartspecification,,-inwhic v F'gure l jisia ing onemannerof mounting the reeds. Fi 3 is a plan view, with thecover. remove showingthe interior construction. Fig-4 is a verticalcross-section on the line IV IV of Fig.v 3. Figs 5 is a similar view onthe line V V of Fig. -1. Fig. 6 is a cross-sectional detail view showingmechanism for producing a ray of light upon vibration of any one reed.Fig; 7 is a sectional plan view of this construction, showin thelight-aperture, reed terminals, and re ector. Fig. 8 is adetail view ofthe upper portion of one. of the reeds pro-- vided with a buttonofdistinguishing color.

Fig. 9 is a cross-sectional view similar to Fig. 5, showing aconstruction em loying oppo- *sitely-located armatures for t e purposeof synchronizing: Fig. 10 is a sectional detail view illustratin onemanner of mounting I the reed-bar an of controllingits vibration.

Fig. 11 is a sectional-plan ,vi'ew indicated by the line XI XI ofFig-'9.- -FigQ12 is a diagrammatic view showing the application of myinvention toa generator. My-inventi-on refers to improvements in freuency-meters for indicating directly on a sca e-the frequencyof analternating circuit.

The princi 1e of the. invention is based on the laws of armonicvibration wherein reeds or strings having a natural rate of vibrationwhen corresponding to an imposed or in-. yibrate activelyin sympathyduced rate will therewith. p v,

Electricians, and particularly those in charge of alternating-currentstations, have long recognized. the need for an instrument which wouldindicate the frequency of the circuit accurately within one alternation..The reasons for this are:

l fact that a system 'will work most satisfactorily and efficiently whenrunning at the rate of alternation for which the system wasSpecification of Letters Patent. r licaticn filed December 7 1904.Serial No. 235,875.

p e 'dfayimages Fig.- i a detail .cr0ss--, c m fi w. On the line-II. IIof Fig. 1 show Patented Sept. 18, 1906.

designed, and more particularly so when the current'is supplied tomotors and other apparatus having coils which comprise aninductive-res1stance'. I v

Second. Where a. c.- generators are desired to run in arallel, itresults in a saving of time to ave "an instrument which will indicatethe fre "uency accurately over a sufficient range, so t at thegenerators can I be brought into step without resorting to theslowmethod connected, with synchronizing- 'lamps..

Nly invention has a special advantage in that two such'generators can beconnected and will indicate their respective frequency on the same dialor scale, thus considerably facilitating the synchronizing operation.

Referring to the drawings wherein the in vention is illustrated, 2represents the base, of any suitable construction, preferably circular,and provided with up er faces adapted to receive and support t e variousportions, which are'in'closed within a surrounding upper case 3, havingan inserted glass 4, adapted to expose the indicating-reeds.

'5 is the reed-bar, in which are rigidly mounted the reeds 6, ofsuitable material and arranged in aduated lengths, the dimensionsthereof eing such that the rate of vibration of the reeds willsuccessively increase or decrease from one end to the other in the samegeneralmanner as the reeds of a musi cal instrument. The upper portionsof the reeds are preferably provided with an indicating-semaphore 7 orother signal device adapted to show by. contrast with the stationaryreeds when any particular reed is vibrated, and these are arranged inrelation to a graduated dial plateor scale 8. (Figs. 1 and 5.) r

In the drawings I-have shown the complete bar of reeds arranged, say,for; a sixtycycle circuit, the center reed opposite that point in thescale or dial marked 6O having respond to sixty cycles from the factthat the machine now to be described is constructed with a non-polarizedcoil and will consethe cycle, as it would if it we're'built with a coiland an armature suitably polarized. This reed having a rate of onehundred and twenty vibrations a second when the mechanism of the circuitconnected to the instrument is exactly sixty cycles, will vibrate in anatural rate of vibration of, sa one hun- 'dred and twenty per second. T's will corquently operate on alternationsinstead of on IIO 10 cientrange for the purposes of the instrwment, while the difierences in=vibratpry rate to which the reeds are tuned issuch' as to in-- sure aproper degree of accuracy in the read-- mgr v I The reed-bar 5 ismounted in any suitable manner, so as-to be sensitive to the influenceof magnetic force and Fig. 5 isshown'as mounted betweencushioningebearings 9, of rubber or other suitable material, beingise 2ocured bys'crew 10, apressur espringl 1 1 being provided to limit orrestrain its movement.

The reed-bar is provided with an armaturebar 1 2-, rigidly securedto itin any suitable manner and located within the magnetic'im These coilsare connected in series with the motor by means of' the' usual wires,the case being provided with binding posts 14 for attachment;therewith--Variations in potential, acting through the coils 13 at so many statedperiods per second, will impart a vibration to the reed-bar 5'and reeds6 at a corresponding rate per second, the reed-bar vibrating under thespring 1-1 as a fulcrum. -5 In Fig I have showna construction Where thereed-baris provided-With an arm15;, connected witha'springediaphragm 16which acts to hold the reed-bar in position while allowing freedom ofmotion and also SGIV'BSthG added purpose'of absorbing any false vibraconjunction with the diaphragm to respondand' coact with the varyingrates of vibration imparted to the reedbar by varying rates infrequency; second, it operates when 5 5 properly adjusted to counter-actto a certain extent the time effect or that factor of a lengthening ofthe true wave of potential which is caused by leading orlagging currentsgenerally found to'be superimposed on a-regular current in a system,acting: in this respect somewhat as a condenser placed' in alternatingcircuitswill act to neutralize the efiect of lagging currents caused byself-induction of the system; third, in its adjust- 6 5 ment it acts inconjunction with the distance tion that may be set up either bythe-acting of the magnet-poles of the armature to properly regulate theamplitude of vibration of the reed-barl 1 In Figs. 9 and 10 I have showna modified construction of the mountin of the reed-"7o bar employingthin springlades 21, prov jectin'g'into' one or both sides oftliebearingbase, thereby providing a very sensitive support subject tothe magnetic influence described. In the construction shown in. Fig; 2 asingle such bladei's' used-"at onesside only. The reeds 6 are"preferably constructed oftemp'ered steel or other suitable ma/BeriailiDifierence in the vibratory reeds to which they are tunedis-such-as-toinsure a roper degree oi accurac in=the reaxling',-an thereare many other actorsother thanythaaofi mere natural rate of vihrationwhieh 'muat be taken into consideration in theconstrmh tion andproper-'proportioning ofthereede for instance, as to sensitivene-ssworthat property of the reed vibrating; in -harmony with an imposediforce;wherehy it-will cease or stopsuch vibration 'on aeertailn slightthe imposed force. Thusthe'reedcawbeso constructed, proportioned-L andmounted I that it will vi brate'activeliii allowing i'i'teelf tohe-forced-intoaetivevi ration even when the diflerence between-itsnatural rate and 5 that of the imposedforce is twooreven or morevibrationspensecon d while it can also be constructed so that it-will'start-or stop vibrating. on so-slighta- (lifierenoe-ai onevibration-in-eightor ten-seconds betwee-n 10o its "ow-n rate andthatch-theimposedforce' with which itis designed to vibrate il-t-harmony These;- properties depend upon the length, disposition of the Weihi1," thematic:

rial, and the cbnditionthereo otwhich-the I reed is constructed and alsouponthe weight? shape nateifial anddisposition-of the weight w of thebarwhich supports'tihe'reedsgwupon the adjustingspringy size 0t the-diaphr'Ill-"16"; and position of the-'coil-.- The bar 0- reed's; having. beentuned to-the varying rates of vibration; and-"properly adjusted as--' te-sew sitiveriess and amplitude; ofvibration, tlfie visual effect upon acontinuous variation-of rate of alternation when connectedwith the rx 5circuit Willabe intheca/se-otchangefrom-a lower to a'- higher rate toproduce; awave of a fvibrations moving from left to right on the tips 7of the vibrating reed opposite the scale. The rapidity ofvibrationissutzhthat the eflect on the eye isa=;mere lengthening of; thereed-tip; which-will'be plainly discernible opposite the graduatedscale; Ae Va "rious modifications-of the reed-tilp n may be employed Ido not desire to'be mited to" any particular'form of construction and'inFig. 8 have illustrated a reed; provided with;

asmall head or button- 2-2, of white material: or'any contrastingcolorfladapted to be-"im r l I I i ed to be uncovered upon vibration,allowing a.

ray to be projected u wardly against the under side of an inclinereflector 27 and thence outwardly across the indicating-dial. By thisconstruction a visible indication is immedi-' ately produced which isreadily discernible in the dark. The coils maybe adjusted with relati onto the armature-bar by means of a setscrew 28, passin through a slot 29of the coil-base 30,whi e the reed-bar, the dial-supports, and thevarious other elements of the device are suitably secured and attached,as shown and described. I

In- Figs. 9 and HI have shown a construction employing a doublearrangement of coils 13, the reed-bar being providedwith correspondingdouble armature-bars 12, such arran ement being capable of beingconnected wit two generators for the purpose of synchronizing- In .thisarrangement where two oppositely-mounted coils are used, each of whichis connected in its respective circuit,

the double armature 12 acts to-impart vibration on coinciding impulsesin opposing directions, and in this form of instrument are secured thebest results on atwo-phase circuit, the enerators being connected. Onthe first an second phase, respectively, in order that the two phasesshall be ninety degrees apart and so reinforce, extend, or counteracteach other when both are in step, it

follows that in order that'the vibration of the reed which both rates ofalternation affect simultaneously when in step will'be increased insteadof'diminishedi To secure the same results, a double-wound single coilmay be used, answering the same purpose,

but with this difference, that it can-be connected with a single-phasemultiple machine, the impulses in such case acting in the same Also incases where the instrument is used on a three or more phase curcuit therates can be and are sometimes necessarily tuned to some one harmonicresulting from the'coactin g electromo'tiveforces, such being especiallythe case when three or four phases are reproduced by difl'erent Wind-'ings on the same machine.

While in the various forms of construction which I have shown anddescribed provision has been made for such conditions as usually ariseand as I have explained, I do not desire to be limited thereto, as theprinciple of the invention may be embodied in various other forms insome of which it is better adapted to certain conditions than others,and I desire to include any formor arrangement whereby.

the frequency of one or more circuits is registered by the arrangementof a bar of reeds as described, in such relation to the circuit orcircuits that they are vibrated by and vibrate in unison with thevarying rates of al-.

ternation and undulation in cases where the alternating current could betransformed to a flow in one direction by any means.

The invention is not limited to the specificuse described, but may beemployed. for de termining the speed of generators where, in

conjunction with an alternator,'it will when properly graduated show thespeed of the directingpulley of the alternator.

The invention may be employed in connection with any suitable recordingmechanism, as, for lnstance, a traveling band of paper adapted to bevisually affected by the passage of a circuit roduced' by the vibrationof the various ree s, as shown in my prior patent, No. 636,685, forweight and pressure recordin' apparatus What claim is 1. In afrequency-meter, the combination with an armature-bar provided with aseries. of indicating-reeds and supplemental cushw ioning mechanism forthe bar, of a magnetic coil in operative relation to the bar, and meansfor establishing a circuit through the coil, substantially as set forth.

2. In a frequency-meter, the combination with an armature-bar mounted onsupplemental sensitive supporting-blades and'provided with a series ofindicating-reeds, of a magnetic coil in operative relation to the bar,an means for establishing a circuit through the coil, substantially asset forth.

3. In a frequency-meter, the combination with a series ofindicating-reeds and a su portin -bar therefor, with a base and suppementa means for sensitively supporting the bar, of a magnetic coil .ino eratlve relation thereto, and meansfor esta lishing a circuit 'throu hthe coil, substantially asset forth.

4. na frequency-meter, the combination of an armature-bar provided witha series of vibrating reed's, resiliently mounted adjusting mechanismadapted to control the vibration of the bar, and a magnet in operativerelation to the bar, substantially as set forth.

5. In a'frequency-meter, the combination of an armature-bar providedwith sensitive resilient supporting mechanism and a bearing ortion, adiaphragm arranged to support sa1 bearing portion, adjusting mechanismfor said bearing portion, a series of indicatingreeds connected with thearmature-bar, and a magnet adapted to impart vibration to the bar andreeds, substantially as set forth.

6. In a frequency-meter, the combination of an armature-bar providedwith sensitive resilient supporting mechanism and a bearing ortion, adiaphragm arranged to support a magnet adapted to impart vibration tothe bar and reeds, with means for adjusting the magnet, substantially asset forth.

7. In a frequency-meter, the combination of a registering-dial, anarmature-bar provided with sensitive resilient supporting mechanism,means for controlling the vibration of the bar, a series ofindicating-reeds connected with the armature-bar and ar ranged inoperative relation to the register- ,in -dial, and a magnet adapted toimpart vi ration to the bar-and ree s, substantially as set forth.

8, The combination with a source of'light and apertures therefor, of aseries of vibrat- 15 in reeds adapted to uncover saidapertures, sustantially as set forth.

. 9. The combination with a source of light and apertures therefor, of aseries of vibrating reeds ada ted to uncover said a ertures, with areflecting device and a dial-p ate, substantially as set forth.-

In testimony whereof I aflix my signature in presence of two witnesses.

Witnesses:

W. C. CARMAN, G. GREENWOOD.'

EDWARD. MQGARVEY, 7

